Real Time Moving Map Displays Assist Police Helicopter Dispatch

Dianne Haley

Abstract

The Calgary Police Service has used a helicopter for a number of years to assist in the apprehension of offenders and other public safety activities. Part of the instrumentation of the helicopter included a PC with a moving map display. In 2001, the GIS Centre of Excellence used Esri Map Objects, shapefiles and GPS to provide an application to be used by the flight crew to locate, in real time, the location of a target address relative to the position of the helicopter. This presentation will discuss the development and use of this application, and will demonstrate the results.


Background

The Calgary Police Services helicopter, known by the call sign HAWC1, was the first Canadian municipal police helicopter. Its acquisition was a direct result of the Helicopter Air Watch for Community Safety (HAWCS) project.

In 1992, the Calgary Police Service began investigating the use of helicopters for municipal police work. In October of that year, Constable Rick Sonnenberg was killed in the line of duty while laying a spike belt across a major highway through Calgary, trying to stop a speeding stolen vehicle. In 1994, Lisa Barrett, Sonnenberg’s sister, approached the Calgary Police Service with the idea of starting a memorial for her brother. She was convinced that he would be alive if a helicopter had been available to assist in the pursuit of the vehicle involved in her brother’s death. She established the Constable Rick Sonnenberg Memorial Society to raise funds for a police helicopter, and the HAWCS project was born. Within a year, the HAWCS group had raised $1.5 million and had purchased a suitable helicopter.

On May 17, 1995 the helicopter was flown to Calgary from Mesa Arizona. It was outfitted with specially designed equipment to make it an effective law enforcement and crime prevention tool. On June 30, the HAWCS project presented the helicopter to the Calgary Police Service; it was on the job that day involved in a search for an individual involved in a shooting in a downtown park.

On July 16, 1995, HAWC1 was officially put into operation and the Air Services Unit of the Calgary Police Service, which includes the helicopter and the flight crew, was formed. In February 1997, The Calgary Police Service Air Services Unit was presented with the McDonnell Douglas Law Enforcement Award.

HAWC1 patrols today, responding to 20-25 complaints each night that it is operational.

The Helicopter

HAWC1 can respond to most crime scenes within the city limits in less than 90 seconds. It can engage in high-speed pursuits with little risk to officers or the public. HAWC1 also assists in search and rescue efforts, often accomplishing them in 1/15 of the time of a ground search.

HAWC1 has assisted the Calgary Fire Department and Calgary Emergency Medical Services by:

HAWC1 is a McDonnell Douglas MD520 Notar. It has 4 seats, but one of those spaces has been used for onboard computer equipment. It can fly up to two hours without refueling, can cross the entire city in 3 minutes, and has no tail rotor, making it one of the quietest helicopters.

HAWC1 is equipped with a Nightsun Spectrolab SX16 searchlight with adjustable focus, which can illuminate an area the size of a baseball diamond and can focus on openings as small as a window. It is also equipped with a Wescam 16DS infrared camera, which can detect objects or people hiding in the dark, or traces of heat such as hot spots in a fire or footprints in the snow. HAWC1 also has advanced avionics and radio equipment, a dual-cone public address and siren system, a cargo hook and a Bambi bucket water drop system.

Moving Map System

The HAWC1 helicopter is also equipped with a Global Positioning Satellite (GPS) receiver and a Moving Map System/Application. This combination of technologies has allowed the flight crew to pinpoint the location of target addresses within seconds. Prior to January 2002, the Moving Map application was based on a DOS platform. In January of 2001, The City of Calgary’s GIS Centre of Excellence (GISCOE) was approached and asked to investigate Windows-based alternatives for the Moving Map application. There were a number of reasons for this request, not the least of which was an upgrade to the HAWC1 computer systems. In addition, the small, third party company that originally developed the previous Moving Map application was no longer in business to provide upgrades to the application. Nor were they able to ensure that updated data was made available to the application. The client department requirements included developing a windows-based application that used the corporate GIS tools and data and which would be supported by the Information Technology infrastructure at The City of Calgary.

The HAWC1 Flight Crew and Flight Engineer originally requested a version of an ArcView application that had been made available to the Calgary Police Service officers in cruisers. This application was essentially an address and intersection search on a geocoded road network. But after a few in-depth discussions with the flight crew, it became apparent that more functionality was needed. In addition to the ability to find any address within city limits, a number of other capabilities were initially requested:

Option 1

Our first solution to this request was to investigate the use of ArcView with the Tracking Analyst Extension. A project was developed that included a function-key-based user interface accessing the Calgary road network that had been geocoded with the Calgary Street Style we had developed in-house. Both address and intersection searches were supported, and Tracking Analyst handled the sample GPS log data supplied by the HAWC1 Flight Engineer. However, in the midst of testing, HAWC1 replaced its GPS receiver with a unit whose signal was not supported by Tracking Analyst. At this point, GISCOE application developers were asked to assist with the endeavor, and code was written to capture and process the GPS signal for map display. Even with this slight delay, a project/application was demonstrated to the Flight Engineer within a month.

Then the realities of developing software for use in helicopter night flights were introduced to the mix. A black background for the map view was requested. While not a difficult problem to overcome, we discovered an inherent limitation in ArcView that did prove to be a major obstacle, threatening to stop the project. With each map view pan or zoom, the view window was emptied of colour (i.e. became white) before the black background and the map was refreshed. This emulated a flashing situation, much akin to a strobe light, something that was totally unacceptable for night flight. After contacting the user community and tapping into various sources at Esri Redlands, GISCOE was forced to reconsider the development direction, and proceeded with Option 2 in October 2001.

Option 2

Our second approach to the problem was to develop a Map Objects application. Through the creative reuse of appropriate modules of pre-existing code from Esri Sample Applications, the essence of Option 2 was delivered within a week. The application permits the Flight Crew to locate, in real time, the location of a target address relative to the position of the helicopter. This application had all the functionality of Option 1 and more, and supported user interaction through the use of function keys and a mouse. No longer was the black background of the map view display interrupted by the flash of white as the view panned or zoomed. And as the Flight Crew became more aware of the corporate spatial data that was available for use, more layers of information were added to the solution; over twenty-five themes of information are now used by the application.

The application has been used in flight since January 2002. It has been fine-tuned during field-testing and in two in-hanger presentations and brief training sessions. While user documentation has been provided to the Flight Crew, the minimal training requirements have meant that few of the crew have read the document. All display variables, including zoom and pan scales, theme symbology and scale display dependencies are controlled in an INI file. This means that, if need be, the Flight Crew or the Flight Engineer can change these values without the assistance of an application developer or staff from GISCOE. The application supports search by address, intersection, GPS coordinates and Latitude/Longitude values. City Emergency Service organizations, including the Calgary Police Service, often respond to incidents past the corporate city limits, so rural data has been obtained for use in HAWC1. This has become increasingly important in light of the G8 Summit held in the Calgary area in June 2002. The Flight Crew has also been provided with the ability to log a flight so that it may be played back in simulation mode at some later date. And a 1-KM search grid has been added to the list of available data layers, as well as the G8 No-Fly zone.

Conclusion

It is extremely satisfying to be able to put GIS functionality into the hands of an excited, if somewhat small, user community. It is particularly gratifying to support the men of HAWC1 and the Air Services Unit, and the valuable service they provide for the citizens of Calgary and the area. And it was refreshing, after an evening in-hanger training session, to hear members of the Flight Crew say that they wished they were flying that evening. While the application itself may seem rather simplistic, it is filling a unique business requirement.


Author Information Dianne Haley, Corporate GIS Business Consultant
GIS Centre of Excellence #8304
The City of Calgary
PO Box 2100, Stn M
Calgary Alberta
Phone: 403-268-4890
Fax: 403-268-8120
Email: dianne.haley@gov.calgary.ab.ca